Has anyone used a tune programmer on their H3 with the 5.3? If so what brand tuner did you buy and did it do what you wanted?

I’d like to use one mostly to firm up the transmission shift points, and to have it hold the gear a little longer when going up a grade.

2009 H3 5.3

 

I use 3 upto 60mph, D on the highway.

3 (Third): This position is also used
for normal driving.
You might choose 3 (Third) instead
of D (Drive) when driving on hilly or
winding roads, or when towing a
trailer, so there is less shifting
between gears.